Method for manufacturing a midsole formed from two preforms

ABSTRACT

A method of manufacturing a midsole for an article of footwear includes placing first and second preforms in a first mold, closing and heating the first mold to produce a midsole preform with a peripheral preform flange, removing the midsole preform from the first mold and allowing it to further expand and cool, placing the midsole preform in a second mold, with a volume of a midsole recess of the second mold being less than a volume of the midsole preform, and a volume of a peripheral recess of the second mold being less than a volume of the peripheral preform flange, closing the second mold thereby compressing the midsole preform and the peripheral preform flange, and heating the second mold to form a midsole with a peripheral flange, allowing the second mold to cool, opening the second mold, and cutting away a peripheral flange of the midsole.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a continuation application of application Ser. No.15/353,903, filed on Nov. 17, 2016, which is incorporated herein byreference in its entirety.

FIELD

Aspects of this invention relate generally to a method of manufacturinga midsole and, in particular, manufacturing a midsole of two preforms,which may have different colors.

BACKGROUND

Conventional articles of athletic footwear include two primary elements,an upper and a sole assembly. The upper provides a covering for the footthat comfortably receives and securely positions the foot with respectto the sole assembly. In addition, the upper may have a configurationthat protects the foot and provides ventilation, thereby cooling thefoot and removing perspiration. The sole assembly is secured to a lowerportion of the upper and is generally positioned between the foot andthe ground. In addition to attenuating ground reaction forces, the soleassembly may provide traction, control foot motions (e.g., by resistingover pronation), and impart stability, for example. Accordingly, theupper and the sole assembly operate cooperatively to provide acomfortable structure that is suited for a wide variety of activities,such as walking and running. An insole may be located within the upperand adjacent to a plantar (i.e., lower) surface of the foot to enhancefootwear comfort, and is typically a thin, compressible member.

The sole assembly may incorporate multiple layers. Some articles offootwear include only a midsole, while others may also include anoutsole secured to a bottom surface of the midsole. The midsole, whichis conventionally secured to the upper along the length of the upper, isprimarily responsible for attenuating ground reaction forces. Themidsole may also form the ground-contacting element of footwear. In suchembodiments, the midsole may include texturing, such as projections andrecesses or grooves, in order to improve traction. The outsole, whenpresent, forms the ground-contacting element and may be fashioned from adurable, wear-resistant material.

The midsole may be primarily formed from a resilient, polymer foammaterial, such as ethyl vinyl acetate (EVA), that extends throughout thelength of the footwear. The properties of the polymer foam material inthe midsole are primarily dependent upon factors that include thedimensional configuration of the midsole and the specificcharacteristics of the material selected for the polymer foam, includingthe density of the polymer foam material. By varying these factorsthroughout the midsole, the relative stiffness and degree of groundreaction force attenuation may be altered to meet the specific demandsof the activity for which the footwear is intended to be used. Inaddition to polymer foam materials, conventional midsoles may include,for example, one or more fluid-filled bladders and moderators.

The midsole may be formed of two or more portions, with some or all ofthe portions having different colors. When a midsole is formed in a moldassembly, such as with EVA, the color or boundary line between thedifferent colored portions may bleed, decreasing the aesthetic appeal ofthe footwear.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is an elevation view of a midsole formed from two preforms.

FIG. 2 is a section view of first and second portions of a first moldused to form the midsole of FIG. 1.

FIG. 3 is a plan view of the first portion of the first mold of FIG. 2.

FIG. 4 is a section view of the first and second portions of the firstmold of FIG. 2, shown with first and second preforms positioned in apreform recess of the first mold.

FIG. 5 is a section view of the first mold of FIG. 2, shown in a closedposition after the first and second preforms have expanded and become amidsole preform.

FIG. 6 is a section view of the midsole preform of FIG. 5, shown afterbeing removed from the first mold.

FIG. 7 is a section view of a second mold used to form the midsole ofFIG. 1, shown with the midsole preform of FIG. 6 being compressedtherein.

FIG. 8 is a section view of the midsole formed in the second mold ofFIG. 7, shown after being removed from the second mold.

FIG. 9 is an elevation view of the midsole of FIG. 8, shown after havinga peripheral flange of the midsole cut away.

The figures referred to above are not drawn necessarily to scale, shouldbe understood to provide a representation of particular embodiments ofthe invention, and are intended to concisely illustrate the principlesinvolved. Some features of the mold assembly used to form a soleassembly formed of different preforms and related methods of manufacturedepicted in the drawings have been enlarged or distorted relative toothers to facilitate explanation and understanding. In general, the samereference numbers are used in the drawings for similar or identicalcomponents and features shown in various alternative embodiments. Moldassemblies used for forming midsoles as disclosed herein would haveconfigurations and components determined, in part, by the intendedapplication and environment in which they are used.

DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS

It would be desirable to provide a midsole formed from two or moreportions and a method and mold for manufacturing such a midsole thatreduces or overcomes some or all of the difficulties inherent in priorknown devices. Applicant recognizes that the principles of the inventionmay be used to advantage to provide a method of manufacturing a midsoleformed of portions having different colors as well as differentperformance characteristics.

In accordance with a first aspect, a method of manufacturing a midsolefor an article of footwear includes placing first and second preforms incontact with one another in a preform recess in a first mold, first andsecond portions of the first mold cooperating to define the preformrecess and a peripheral overflow chamber extending about a periphery ofthe preform recess; closing the first mold by positioning the first andsecond portions in contact with one another; heating the first mold fora predetermined period of time at a predetermined temperature such thatthe first and second preforms expand within the preform recess and intothe peripheral overflow chamber to produce a midsole preform with aperipheral preform flange extending about a periphery of the midsolepreform; removing the midsole preform from the first mold; allowing themidsole to further expand and cool; placing the midsole preform in amidsole recess of a second mold and the peripheral preform flange in aperipheral recess of the second mold, first and second portions of thesecond mold cooperating to define the midsole recess and the peripheralrecess extending about a periphery of the midsole recess, with a volumeof the midsole recess being less than a volume of the midsole preform,and a volume of the peripheral recess being less than a volume of theperipheral preform flange; closing the second mold by positioning thefirst and second portions in contact with one another, therebycompressing the midsole preform and the peripheral preform flange toproduce a midsole with a peripheral flange; heating the second mold fora predetermined period of time at a predetermined temperature; allowingthe second mold to cool; opening the second mold; and cutting away theperipheral flange of the midsole.

In accordance with another aspect, a method of manufacturing a midsolefor an article of footwear includes placing a first preform having afirst preform peripheral flange and a second preform having a secondpreform peripheral flange in contact with one another in a preformrecess in a first mold, the first and second preforms being positionedin a preform recess in the first mold, a first recess formed in a firstportion of the first mold and a second recess formed in a second portionof the first mold cooperating to define the preform recess, the firstand second preform peripheral flanges being positioned in a peripheraloverflow chamber of the first mold, a first overflow recess formed inthe first portion of the first mold and a second overflow recess formedin the second portion of the first mold cooperating to define theperipheral overflow chamber; closing the first mold by positioning thefirst and second portions in contact with one another; heating the firstmold for a predetermined period of time at a predetermined temperaturesuch that the first and second preforms expand within the preform recessand the first and second preform peripheral flanges expand within theperipheral overflow chamber to produce a midsole preform with aperipheral preform flange extending about a periphery of the midsolepreform; removing the midsole preform from the first mold; allowing themidsole to further expand and cool; placing the midsole preform in amidsole recess of a second mold and the peripheral flange in aperipheral recess of the second mold, a first recess in the firstportion of the second mold and a second recess in the second portion ofthe second mold cooperating to define the midsole recess, a firstperipheral recess in the first portion of the second mold and a secondperipheral recess in the second portion of the second mold cooperatingto define and the peripheral recess extending about a periphery of themidsole recess, with a volume of the midsole recess being less than avolume of the midsole preform and a volume of the peripheral recessbeing less than a volume of the peripheral flange; closing the secondmold by and compressing the midsole preform and the peripheral preformflange by aligning the first recess in the first portion of the secondmold and the second recess in the second portion of the second mold andbringing the first and second portions into contact with one another toform a midsole with a peripheral flange; heating the second mold for apredetermined period of time at a predetermined temperature; allowingthe second mold to cool; opening the second mold; and cutting away theperipheral flange of the midsole.

By providing a method for manufacturing such a midsole, footwear withimproved aesthetic appeal and/or performance can be produced. These andadditional features and advantages disclosed here will be furtherunderstood from the following detailed disclosure of certainembodiments.

A sole assembly or midsole 10 for an article of footwear is depicted inFIG. 1. It is to be appreciated that in certain embodiments, an outsole(not shown) may be secured to the bottom surface of midsole 10, andmidsole 10 may be secured beneath an upper, in conventional fashion. Inother embodiments, the bottom surface of midsole 10 itself may serve asthe ground-engaging portion (or other contact surface-engaging portion)of an article of footwear.

Midsole 10 serves, among other things, to provide shock-attenuation andenergy-absorption for an article of footwear. Midsole 10 can be used forany of various articles of casual footwear having configurationssuitable, for example, for walking or lounging. Midsole 10 may also beincluded as part of a wide range of athletic footwear styles, includingshoes that are suitable for soccer, running, basketball, baseball,cross-training, football, rugby, tennis, and volleyball, for example. Anindividual skilled in the relevant art will appreciate, therefore, thatthe concepts disclosed herein with regard to midsole 10 may be appliedto a wide variety of footwear styles, in addition to the specific stylesdiscussed herein and depicted in the accompanying figures.

Midsole 10 includes a first portion 12, which may be formed of a firstmaterial and may have a first color, and a second portion 14, which maybe formed of a second material and may have a second color. The secondcolor may be a different color than the first color. In the illustratedembodiment, second portion 14 is positioned above first portion 12.However, it is to be appreciated that first portion 12 and secondportion 14 can be oriented in any desired manner with respect to oneanother.

The discussion of midsole 10 herein primarily describes midsole 10 asbeing formed of a first portion 12 and a second portion 14. However, itis to be appreciated that midsole 10 can include more than just thesetwo portions.

In certain embodiments, the first and second materials may also havedifferent physical properties from one another and, therefore, differentperformance characteristics. For example, the hardness of the variousportions may be different from one another. It is to be appreciated thatany of the known physical properties or performance characteristics forsole assemblies can be different for the different portions of midsole10, thereby altering the support, cushioning, load carrying capability,wear characteristics, and tread life of midsole 10, for example. Othersuitable physical properties or performance characteristics will becomereadily apparent to those skilled in the art, given the benefit of thisdisclosure.

For purposes of reference in the following description, midsole 10 maybe divided into three general regions: a forefoot region 16, a midfootregion 18, and a heel region 20. Regions 16-20 are not intended todemarcate precise areas of midsole 10. Rather, regions 16-20 areintended to represent general areas of midsole 10 that provide a frameof reference during the following discussion. Although regions 16-20apply generally to midsole 10, references to regions 16-20 also mayapply specifically to first portion 12, second portion 14, or individualcomponents or portions of midsole 10.

For purposes of reference, midsole 10 includes a medial side 22 and anopposite lateral side 24. Lateral side 24 is positioned to extend alonga lateral side of the foot (i.e., the outside) and generally passesthrough each of regions 16-20. Similarly, medial side 22 is positionedto extend along an opposite medial side of the foot (i.e., the inside)and generally passes through each of regions 16-20.

As noted above, a separate outsole member may be secured to a bottomsurface 26 of midsole 10, and serve as the ground-engaging surface ofthe footwear. In other embodiments, bottom surface 26 itself may serveas the ground-engaging surface of the footwear.

In known fashion, an upper may be secured to the upper surface ofmidsole 10 in order to fully form the footwear. The upper may be securedto midsole 10 with an adhesive, or in any other known fashion. The upperis not shown here as those skilled in the art are well aware of how anupper is secured to a midsole, and, therefore, such a drawing is notnecessary for an understanding of the invention.

The materials used to form first portion 12 and second portion 14 ofmidsole 10 may be injection phylon (ethylene vinyl acetate or “EVA”).The EVA may have a vinyl acetate (VA) level between approximately 9% andapproximately 40%. Suitable EVA resins include Elvax®, provided by E. I.du Pont de Nemours and Company, and Engage™, provided by the DowChemical Company, for example. In certain embodiments, the EVA may beformed of a combination of high melt index and low melt index material.For example, the EVA may have a melt index between approximately 1 andapproximately 50.

As used herein, the term approximately is intended to mean about orapproximately, within the constraints of sensible, manufacturingtolerances, commercial engineering objectives, costs and capabilities inthe field of footwear manufacturing.

The EVA may also include various components including a blowing agent.The blowing agent may have a percent weight between approximately 10%and approximately 20%. Suitable blowing agents include azodicarboamide,for example. In certain embodiments, a peroxide-based curing agent, suchas dicumyl peroxide may be used. The amount of curing agent may bebetween approximately 0.6% and approximately 1.5%. The EVA may alsoinclude homogenizing agents, process aids, and waxes. For example, amixture of light aliphatic hydrocarbons such as Struktol® 60NS,available from Schill+Seilacher “Struktol” GmbH, may be included. TheEVA may also include other constituents such as a release agent (e.g.,stearic acid), activators (e.g., zinc oxide), fillers (e.g., magnesiumcarbonate), pigments, and clays.

Other suitable materials for first portion 12 and second portion 14 willbecome readily apparent to those skilled in the art, given the benefitof this disclosure.

As noted above, first portion 12 may be formed of a material having afirst color, while second portion 14 may be formed of a material havinga second color that is different than the first color. First and secondportions 12, 14 may also have different values for various physicalproperties in order to alter or enhance the performance characteristicsof the footwear. For example, first and second portions 12, 14 may havedifferent hardnesses, densities, specific gravities, or any otherbeneficial physical property. Other suitable physical properties forwhich the first and second portions may have different values willbecome readily apparent to those skilled in the art, given the benefitof this disclosure.

As seen in FIG. 1, a color line or boundary 28 is formed at the boundaryor interface between first portion 12 and second portion 14 of midsole10. It is desirable to minimize the bleeding between the two differentcolors of first portion 12 and second portion 14, which can occur duringthe molding process. It is to be appreciated that the aesthetics ofmidsole 10 are improved by minimizing bleeding during the manufacture ofmidsole 10.

It is to be appreciated that more than two portions can be used to formmidsole 10, in order to introduce additional colors and additionalperformance characteristics to midsole 10. It is to be appreciated thatany number of colors can be used for different portions of midsole 10.

A first mold or mold assembly 30 used to form midsole 10 is illustratedin FIGS. 2-5, and includes a bottom or first portion 32, and a top orsecond portion 34. A first recess 36 formed in an upper or top surface38 of first portion 32 and a second recess 40 formed in a lower orbottom surface 42 of second portion 34 cooperate to define a midsolepreform recess 44. In the illustrated embodiment, first portion 32,which is positioned beneath second portion 34, forms a bottom surface ofa preform formed in first mold 30, while second portion 34 forms a topsurface of the preform formed in first mold 30. It is to be appreciatedthat in other embodiments, first and second portions 32, 34 can have adifferent positional relationship with respect to one another.

First portion 32 includes a first overflow recess 46 formed in topsurface 38. First overflow 46 recess extends along an entire peripheraltop edge of first recess 36, as seen most clearly in FIG. 3, has a depththat is less than a depth of first recess 36. A corresponding secondoverflow recess 48 is formed in the bottom surface 42 of second portion34, extends along an entire peripheral bottom edge of second recess 40,and has a depth that is less than a depth of second recess 40. The ratiobetween the depths of the first and second overflow recesses and thefirst and second recesses can vary, depending on the particular footweardesign and materials used. First overflow recess 46 and second overflowrecess 48 cooperate to define a peripheral overflow chamber 50 whenfirst mold 30 is closed with first portion 32 and second portion 34 incontact with one another, as seen in FIG. 5.

In one method of forming midsole 10, a first preform 52 and a secondpreform 54 are first formed in known fashion in one or more separatemold assemblies. First preform 52 may have a first peripheral preformflange 53 extending about an entire peripheral upper edge of firstpreform 52. Similarly, second preform 54 may have a second peripheralpreform flange 55 extending about an entire peripheral lower edge ofsecond preform 54. First preform 52 with first peripheral preform flange53 and second preform 54 with second peripheral preform flange 55 arepositioned in midsole preform recess 44 of first mold 30, which has beenheated, with first peripheral preform flange 53 and second peripheralpreform flange 55 being positioned within peripheral overflow chamber50. The interface between first preform 52 and second preform 54, andbetween first peripheral preform flange 53 and second peripheral preformflange 55 is positioned in line with the interface between first portion32 and second portion 34 of first mold 30.

As seen here, first preform 52 and second preform 54 have approximatelythe same thickness. However, it is to be appreciated that the relativethicknesses of first preform 52 and second preform 54 can vary. Thus, asseen in FIG. 1, the relative thicknesses of first portion 12 and secondportion 14 vary along the length of midsole 10. The thicknesses of theportions of midsole 10 and, therefore, the preforms used to producemidsole 10, can vary along footwear 10 to accommodate different designconsiderations, and may also vary based on the particular materialsused.

First preform 52 and second preform 54 combine to form a midsole preform56, with a peripheral preform flange 62 being formed about a peripheryof midsole preform 56, as seen in FIGS. 5 and 6 and described below. Asdiscussed above, in certain embodiments, first and second preforms 52,54 may be formed of EVA.

A release agent may be applied to the exposed surface of first andsecond preforms 52, 54 and/or the surfaces of midsole preform recess 44of first mold 30 in order to facilitate the separation of midsolepreform 54 from first mold 30 after its formation. The release agent maybe a spray release agent or any other suitable release agent. Suitablematerials for the release agent include, for example, siloxane andwater. Other suitable release agents will become readily apparent tothose skilled in the art, given the benefit of this disclosure.

First mold 30 is then closed so that first portion 32 is in contact withsecond portion 34, with first and second preforms 52, 54 seated withinmidsole preform recess 44 and first peripheral preform flange 53 andsecond peripheral preform flange 55 seated within peripheral overflowchamber 50. First portion 32 and second portion 34 of first mold 30 maybe hinged together, or they may be separate elements that are suitablyaligned and placed in contact with one another.

Heat is then supplied to first mold 30 with first preform 52 and secondpreform 54 contained therein for a predetermined period of time. Incertain embodiments, first mold 30 is heated at a temperature ofapproximately 130° C. for approximately 15-20 minutes, thereby causingfirst and second preforms 52, 54 to partially expand into midsolepreform recess 44, and first peripheral preform flange 53 and secondperipheral preform flange 55 expanding into peripheral overflow chamber50. It is to be appreciated that the specific temperature and timeperiod used to form midsole preform 56 in first mold 30 can be varied,in known fashion, depending on the particular EVA, or other material,used. As used herein, the term “approximately” is intended to meanapproximately or about, within the constraints of sensible, commercialengineering objectives, costs, and capabilities in the field of footwearmanufacture.

This expansion forms midsole preform 56 with first portion 58 and secondportion 60, peripheral preform flange 62 extending about a periphery ofmidsole preform 56, and a preform boundary 63 that defines the interfacebetween first portion 58 and second portion 60 and bisects peripheralpreform 62, as can be seen in FIG. 5.

After this heating step is complete, first mold 30 is opened, andmidsole preform 56 with peripheral preform flange 62 further expands inknown fashion after it is removed from first mold 30. The process ofbonding within first mold 30, and the expansion of midsole preform 56and peripheral preform flange 62, can produce bleeding between thedifferent colors of first portion 58 and second portion 60, which maycreate an uneven bleeding line at boundary 63 between first portion 58and second portion 60. The formation of peripheral preform flange 62 infirst mold 30 helps to make the color line at boundary 63 less uneven,and, therefore more aesthetically pleasing.

After midsole preform 56 has stabilized and cooled to ambienttemperature, midsole preform 56 undergoes a compression molding step ina second mold 74. Second mold 74 includes a bottom or first portion 76,and a top or second portion 78. A first recess 80 is formed in an upperor top surface 82 of first portion 76 and a second recess 84 is formedin a lower or bottom surface 86 of second portion 78 cooperate to definea midsole recess 88. Midsole recess has a volume that is less than avolume of midsole preform 56.

In the illustrated embodiment, first portion 76, which is positionedbeneath second portion 78, forms a bottom surface of midsole 10, whilesecond portion 78 forms a top surface of midsole 10. It is to beappreciated that in other embodiments, first and second portions 76, 78can have a different positional relationship with respect to oneanother.

A first peripheral recess 90 is formed in top surface 82 of firstportion 76. First peripheral recess 90 extends along an entireperipheral top edge of first recess 80, and has a depth that is lessthan a depth of first recess 80. A corresponding second peripheralrecess 92 is formed in the bottom surface 86 of second portion 78,extends along an entire peripheral bottom edge of second recess 84, andhas a depth that is less than a depth of second recess 84. The ratiobetween the depths of the first and second peripheral recesses and thefirst and second recesses can vary, depending on the particular footweardesign and materials used. First peripheral recess 90 and secondperipheral recess 92 cooperate to define a peripheral chamber 94 whensecond mold 74 is closed with first portion 76 and second portion 78 incontact with one another, as seen in FIG. 7. Peripheral chamber 94 has avolume that is less than a volume of peripheral preform flange 62.

Midsole preform 56 is positioned within midsole recess 88 in second mold74, with peripheral preform flange 62 being positioned within peripheralrecess 92, when second mold 74 is cool, that is, at an ambient or lowertemperature and not heated. Second mold 74 is then closed so that secondportion 44 is in contact with first portion 42. In this embodiment,midsole recess 50, and first and second preforms 56, 58 are sized suchthat first and second preforms 56, 58 are compressed when second mold 74is closed. First portion 76 and second portion 78 of second mold 74 maybe hinged together, or they may be separate elements that are suitablyaligned and placed in contact with one another.

Second mold 74 is then heated for a predetermined period of time. Incertain embodiments, second mold 74 is heated to approximately 140° C.for approximately 15 minutes, thereby forming midsole 10 with firstportion 12, second portion 14 and a peripheral flange 98. The specifictemperatures and time periods used to heat second mold 74 can be varied,in known fashion, depending on the particular EVA, or other material,used.

While second mold 74 is still closed, it is cooled, allowing midsole 10to fully cure and stabilize. This compression molding process providesmidsole 10 with a finished configuration that has the same dimensions asthat of midsole recess 88. In certain embodiments, second mold 74 iscooled in a closed condition for approximately 15 minutes until thetemperature of second mold 74 is below approximately 35° C.

Once midsole 10 is completely stabilized and cured, second mold 74 isopened, and midsole 10 including first portion 12, second portion 14,and peripheral flange 98 is removed from second mold 74. Boundary 28,which is formed at the interface between first portion 12 and secondportion 14 bisects peripheral flange 98. Once midsole 10 is removed fromsecond mold 74, peripheral flange 98 is cut away from midsole 10,leaving boundary 28 between first portion 12 and second portion 14 ofmidsole 10 exposed. It is to be appreciated that midsole 10 may undergofurther finishing steps, as required.

As noted above, providing different physical properties for first andsecond preforms 52, 54, or any other additional preforms and, therefore,first and second portions 12, 14, allows midsole 10 to be customized oroptimized to provide particular aesthetic and/or performancecharacteristics.

Thus, while there have been shown, described, and pointed outfundamental novel features of various embodiments, it will be understoodthat various omissions, substitutions, and changes in the form anddetails of the devices illustrated, and in their operation, may be madeby those skilled in the art without departing from the spirit and scopeof the invention. For example, it is expressly intended that allcombinations of those elements and/or steps which perform substantiallythe same function, in substantially the same way, to achieve the sameresults are within the scope of the invention. Substitutions of elementsfrom one described embodiment to another are also fully intended andcontemplated. It is the intention, therefore, to be limited only asindicated by the scope of the claims appended hereto.

What is claimed is:
 1. A method of manufacturing a molded foam articlefor a midsole of an article of footwear, the method comprising: fillinga mold by placing a first preform having a first volume in a recess in amold, the mold having a mold recess and a peripheral overflow chamber,wherein the mold recess includes a forefoot mold region, a midfoot moldregion, a heel mold region, and a peripheral edge extending continuouslyalong the medial and lateral sides of the mold recess, connecting theforefoot mold region, the midfoot mold region, and the heel mold region,and wherein the peripheral overflow chamber extends continuously aroundthe peripheral edge of the mold recess; closing the filled mold; moldingthe first preform by heating the first preform in the closed mold for aperiod of time and at a temperature such that the first preform expandsinto and fills the peripheral overflow chamber, forming a molded foamarticle having a first portion and a peripheral flange portion; allowingthe molded foam article to cool; and removing the cooled molded foamarticle from the mold recess.
 2. The method of claim 1, wherein a depthand width of the peripheral overflow chamber are uniform around theperipheral edge of the mold recess, and the depth of the peripheraloverflow chamber is uniform across its entire width extending out fromthe peripheral edge of the mold recess.
 3. The method of claim 1,wherein a volume of the mold recess is less than the first volume of thefirst preform.
 4. The method of claim 1, wherein the depth of theperipheral overflow chamber is less than a depth of the mold recess. 5.The method of claim 1, wherein the mold is a two-piece mold including afirst mold piece with a first mold recess and a first peripheraloverflow recess, and a second mold piece with a second mold recess and asecond peripheral overflow recess, the first and second mold recessescooperating to define the mold recess, the first and second peripheraloverflow recesses cooperating to define the peripheral overflow recess,and wherein closing the filled mold comprises aligning the first andsecond mold recesses and bringing the first and second mold pieces intocontact with one another.
 6. The method of claim 1, wherein the firstpreform comprises an ethylene-vinyl acetate foam.
 7. The method of claim1, wherein the step of filling the mold further comprises placing thefirst preform in contact with at least one second preform in the moldrecess, the at least one second preform having a second volume.
 8. Themethod of claim 7, wherein the volume of the mold recess is less thanthe total of the first volume of the first preform and the second volumeof the at least one second preform.
 9. The method of claim 7, whereinthe first preform has a first thickness and the at least one secondpreform has a second thickness, and the second thickness is differentfrom the first thickness.
 10. The method of claim 7, wherein the firstpreform comprises a first polymeric material, and the at least onesecond preform comprises a second polymeric material, and the secondpolymeric material is different from the first polymeric material. 11.The method of claim 7, wherein the first preform has a first color,density or hardness and the at least one second preform has a secondcolor, density or hardness, and the second color, density or hardnessdifferent from the first color, density or hardness.
 12. A molded foamarticle for a midsole of an article of footwear manufactured accordingto the method of claim
 1. 13. A molded foam article for a midsole of anarticle of footwear, comprising: a first portion comprising a firstmolded foam, the first portion including a forefoot region, a midfootregion, and a heel region; and a peripheral flange portion comprisingthe first molded foam, the peripheral flange portion forming medial andlateral edges of the molded foam article and extending continuouslyaround an entire periphery of the first portion.
 14. The molded foamarticle of claim 13, wherein a width and a thickness of the peripheralflange portion are uniform around the entire periphery of the firstportion, and a thickness of the peripheral flange region is uniformacross its entire width.
 15. The molded foam article of claim 13,wherein a thickness of the peripheral flange portion is less than athickness of the first portion.
 16. The molded foam article of claim 13,wherein the first molded foam comprises an ethylene-vinyl acetate foam.17. The molded foam article of claim 13, wherein the molded foam articlefurther comprises a second portion comprising a second molded foam, andwherein the peripheral flange portion comprises the second molded foam.18. The molded foam article of claim 13, wherein the first portion has afirst thickness and the second portion has a second thickness differentthan the first thickness.
 19. The molded foam article of claim 13,wherein the first molded foam comprises a first polymeric material, andthe second molded foam comprises a second polymeric material differentthan the first polymeric material.
 20. The molded foam article of claim13, wherein the first molded foam has a first color, density, orhardness; the second molded foam has a second color, density, orhardness; and the second color, density or hardness is different fromthe first color, density or hardness.